Technically, someone just sending something to your address doesn't make you guilty. They can't get a conviction just on that. So what they do is tell you there's a package they couldn't deliver and need you to come to the post office to pick up. If you come and claim it, they consider that to be acknowledging that you expected the package. If you just insist you're not expecting a package and cut your losses, though, there's not much they can do.

Also, use the post office, not a corporate shipper like UPS or FedEx. The 4th amendment only restricts the government, not businesses.

Of course, with the Trump administration flagrantly ignoring the constitution, all bets are off. You should theoretically be safe, but... Maybe don't tempt the racist gestapo if you're not white.